A conveying device of conventional production apparatus mostly has a flat surface (e.g., on a conveyor belt) to carry a device under test (DUT), such as an outsole of a shoe. For example, when the conventional production apparatus is used to produce an outsole, the outsole is disposed on a surface of the conveying device. However, since the thickness of the outsole is not large, it is difficult for a camera device to distinguish the outsole from the surface of the conveying device. Accordingly, the conventional production apparatus does not have a depth image detection for the DUT (e.g., the outsole), so that the manufacturing yield and production efficiency of the DUT cannot be improved by use of the depth image detection.